package com.kfm.servlet;

import javax.servlet.ServletContext;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
import java.io.IOException;
import java.util.Map;

@WebServlet("/outline")
public class OutlineServlet extends HttpServlet {

    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        String id = req.getParameter("id");

        // 从 application 中获取在线用户列表
        ServletContext application = req.getServletContext();
        Map<String, HttpSession> onlineUsers = (Map<String, HttpSession>) application.getAttribute("online");

        HttpSession httpSession = onlineUsers.get(id);
        if (httpSession != null){
            onlineUsers.remove(id);
            httpSession.invalidate();
            resp.sendRedirect("online");
        }
    }
}
